Construction machines, such as loaders, dozers, material handlers, and the like have work implements, such as buckets, blades, forks and the like movably mounted on the machine frame. An internal combustion engine, which powers the machine and the implements, is resiliently mounted on the frame by engine mounts of a conventional type. The engine is often transversely mounted relative to the direction of machine movement. A cooling system is provided on the machine for cooling the engine. The cooling system includes a radiator and a fan. The radiator is mounted on the frame adjacent an end of the engine and located to one side of the machine. The fan is often located between the end of the engine and the radiator and rotatively driven by the engine. The fan induces cooling air flow to pass through the core of the radiator for engine cooling purposes.
In construction machines, such as discussed above, it is a common practice to drive the machine, particularly the work implement mounted thereon, into the material so that the work implement may be loaded. Impact between the implement and the material causes the transverse mounted engine to rock relative to the frame, in forward and rearward directions, relative to the direction of movement of the machine. Since the fan is connected to the engine, this movement results in relative movement between the fan blade and radiator. In applications where a shroud for directing air flow is provided, this movement results in interference between the fan blades and surrounding shroud. This interference results in fouling of the fan blades and damage to the shroud.
The location of the centerline of the fan relative to the center of the opening in the shroud are ideally aligned. However, in practice, due to design and manufacturing tolerance stack up alignment seldom occurs. In a longitudinally oriented engine application this misalignment maybe acceptable as clearance between the shroud and fan blade tips is adequate to accommodate the maximum amount of misalignment. However, in transversely mounted machine applications, such misalignment is not acceptable. Under the dynamics of machine operation, the combination of rocking movement of the transversely mounted engine and misalignment of the engine and shroud causes fan blade and shroud interference.
It is desirable to maintain the amount of clearance between the fan blade tips and the shroud within a preselected tolerance range in order to maximize cooling efficiency and minimize noise. Unnecessarily, increasing the clearance between the fan and the shroud to accommodate misalignment and engine rocking is not acceptable as it sacrifices efficiency and noise abatement.
The present invention is directed to overcoming one or more of the problems set forth above.